During 1973, the fourth year of an effort to evaluate the effects of three alternative kinds of health care services on three defined populations, a major study of unmet needs for care and services, which included household interviews and extensive health examinations, completed its field work. This is the first phase of a study to be reported in 1974, and to be repeated and completed by December 1978. A blood pressure outcome study continued its activity, as did a program to monitor births, perinatal mortality, and all deaths. A consumer evaluation study was pretested and then fielded, focusing on what defined populations of recently pregnant women thought about the care they and their babies had received. Alongside these efforts there was an updating of the program characteristics of the three alternative health care services which is the major variable for the overall studies.